Pontoon-attaching means



March 12, i929. A. R. STALB, JR

PONTOON ATTACHING MEANS Filed March 14, 1928 gvwemtoz Patented YMar. 12,1929.

UNITED STATES 1,704,111 PATENT OFFICE.

ARTHUR RALSTON STALB, JR., OF FARMINGDALE, NEW YORK, ASSIGNOR 'IO FAIR-CHIL'D AVIATION CORPORATION, OF NEW YORK, N. Y., ACORPORATION OF DELA-WARE. v

' Application filed March 14, 1.928.

. This invention relates to hydroaeroplanes 1n general, and specificallyto attaching means for seaplane pontoons.

In seaplanes the fuselage is frequently supported from a plurality ofpontoons by a series of struts or framework. This framework is usuallyprovided with a plurality of substantially horizontal cross or spacerstruts to which the pontoons are secured. In detachable pontoons thisstrut has heretofore passed over the top of the pontoon. Thisarrangement adds greatly to the parasitic resistance and isunsatisfactory from a construction standpoint. It was with a view toproduce an attaching arrangement which would obviate these objectionsthat the invention of this application was developed.

One of the objects of this invention is to of a supporting strut withinthe streamline' contour of the pontoon thus reducing parasiticresistance.

Another object of this invention is to provide means for detachablyconnecting theY ends of the cross or spacer strut to the pontoons of aseaplane.

Other objects and advantages of this invention will become apparent fromthe following description, claims and appended drawings in which Fig. 1is a view in perspective showin a portion of a pontoon to which thisinventlon is applied.

Fig. 2 is a sectional view transverse to the axis of a pontoon.

As hereinbefore stated, this invention relates to means for attachingpontoons to seaplanes and especially to seaplanes of the Fairchild typewhich are provided with a pair of pontoons attached to the lower end ofcross frames projecting downwardly from the fuselage. Two cross framesare provided,

50 one positioned in front of the other and braced by means of guywires. A pontoon is secured on either side of the center line of thecraft to the lower ends of the cross frames.

This invention relates to the manner in which the cross frames andpontoons are united and provide means for detachably securing sup-vSerial No. 261,515.

since all unions between pontoons and cross frames are similar only onewill be described.

Referring to the drawings, 1 represents a pontoon` such as is commonlyused in the construction of seaplanes. The pontoon is constructed with alongitudinal member or back-bone, 2 to which the ribs 3 and crossbracing members 4 of the pontoon are attached. As has been hereinbeforestated, two pontoons are customarily employed and are 55 attached to theaeroplane fuselage in a manner now to be described.

The aeroplane fuselage is supported from the pontoon 1 by means of aplurality of members 5 which at their lower ends are welded 70 or brazedto the ends of cross pieces or struts 6, two of the members 5 beingprovided for eachl pontoon. The pontoons are arranged parallel to eachother and are held in position, front and rear, by means of the cross-7.5

.pieces or struts 6 to which the supporting members 5 are welded.Suitable guy wires 7 attached to lugs-8I near the ends of membersy 5 and6 serve to brace theV entire structure. This construction is simple andob- S0 Vious and needs no further description here.

The manner in which the pontoons 1 are attached to the cross-pieces orstruts 6 will now be described.l Welded to each end of the cross-piecesor struts 6 is a flanged plate 9 85 which is attached to the back-bone 2of the pontoon by means of two bolts 10 which pass Y through holes inthe plates 9. Secured ton the outer shell of the pontoonql is a formedplate 11 which, as best shown in Fig. 2, is 90 bolted to the back-bone 2by means of the bolts 10, the plate 11 being interposed betweenv theplate 9 and the back-bone 2. The plate 11 forms a shallow pocket ordepression in the outer shell of the pontoon in which the end of thecross-pieces or struts 6 rest. The object of this construction is toreduce the parasitic resistance as `much as possible by making the pointat which the pontoon is attached to the supporting members 5 and 100cross-pieces or struts 6 as -nearly streamline as possible.

The cross-pieces or struts 6 are also detachably fastened to the pontoonby means of a clamping piece 12 which is bolted to 105 ears 13 and 14 bymeans of a bolt 15. A strap piece 16 and bolts 17 clamp the crosspiecesor struts 6 firmly against the yoke 12.

Each of the ears 13 and 14 is bolted to the side of the pontoon 1 bymeans of bolts 18. 110

At the pointlwhere the ears 13 and 14 are V the backbone 2 of thepontoon. A substantially triangular flanged reenforcing plate is securedto the outside of each piece 19 by screws or bolts passing thru theplates 20, the piece 19 and into the rib 3 and interior brace 4. Theseplates serve as attaching members for the ears 13 and 14. The bolts 18pass thru the outer shell of the pontoon and also thru holes in theflanges of plates 20 thus securing theears 13 and 14 to the said plates.

The object of this construction is to stifen the pontoons at the pointswhere the ears 13 and 14 are bolted to the pontoon shell and to transmitthe stress to the shell and to `the backbone 2. In practice it has beenfound desirable to provide a cross bulkhead adjacent the cross frame orrib to which the plates 2O are secured. The bulkhead lies between oneplate 20 and the cross frame. The securing means for the plate 20 ofcourse pass thru the bulkhead and thus hold the parts firmly together.

yIf desired the interior frames may be dispensed with in part orentirely and the strut attaching means secured topbulkheads and thepontoon shell.

It will be apparent from the foregoing description that the majorportion of the ordinaryI landing reaction, being vertical in nature,will be taken by the strut connection adjacent the vertical center planeor backbone of the pontoon. The connection at the side of the pontoonwill, of course, take a proportionate share of this reaction. Inpractice, many landings must be effected while the plane is'driftingsidewise or side slipping to the direction of flight. In such landings aheavy strain is placed on the pontoon and lthe side connection of thisinvention is provided to transmit a large part of this strain to thestrut means. This side connection is preferably placed inorsubstantially in the line of the reaction due to such landing with sideslip but I do not desire to limit myself in this respect.

From the foregoing description, it will be clearly seen that theconstruction shown in the drawings provides a strong and rigid means formounting a hydroaeroplane on its pontoons and that it also provides for.quick and easy removal and replacement ofthe pontoons. Furthermore theconstruction is such that the pointsfat which the cross-pieces andsupporting members are attached offer very little parasitic resistance./It is obvious that if desired the cross member 6 may be arched upwardlyto provide greater wave clearance or may be formed in two parts each ofwhich extends to a point on the airplane fuselage or body much in theorder of ordinary landing gear struts for instance, similar to theFairchild land gear. This will produce a maximum wave clearance whichespecially in planes used on open water is very desirable.

Various changes in the construction of the embodiment illustrated in thedrawings may be made without departing from the spirlt of the invention,and I `do not therefore, desire to limit myself to the specificconstruction shown and described, but to interpret the invention broadlywithin the scope of the appended claims.

What I claim as my invention is:

1. In a device of the class' described, a pontoon having a reentrantpocket formed in the surface thereof, for receiving an attachment strut,strut securing means in said pocket and strut securingmeans adjacentsaid pocket.

2. In a device of the class described, a pontoon having an internalframe, a strut for atceive said strut, and means for securing said strutto said frame member.

3. In, a device of the class described, a pontoon' having an internalframe, a strut for attaching the pontoon to an aircraft body, a pocketformed in the surface of the pontoon and adjacent a member of the frameto receive said strut, means for securing said strut to said framemember, and means for securing said strut to said pontoon externally ofthe pocket.

4. In a device of the class described, a pontoon having a frame and asurface formed with a pocket therein adjacent a member of said frame forreceiving a strut for attaching the pontoon lto an aircraft, and meanswithinsaid pocket for securing said strut to said frame whereby theparasitic resistance is reduced to a minimum.

5. In a quick detachable connection between a pontoon and a strut, meansfor detachably securing said strutdirectly to the pontoon frame andadditional means for detachably securing said strut indirectly to thepontoon frame.

' 6. In a device of the class described, apontoon, strut means forsecuring said pontoon to an aircraft, means for connecting said pontoonto said strut means in the line of vertical reaction of said pontoon inlanding without sfide slip and means for connecting said pontoon to saidstrut means in the line of reaction set up in landing with side slip.

7. Iny a device of the class described, a pontoon, strut means forsecuring said pontoon to an aircraft, means for connecting said strutmeans to said pontoon adjacent thevertical momie center plane of thepontoon and additional means removed from the vertical center plane ofthe pontoon for connecting said strut means to said pontoon.

8. In a device of the class described, a pontoon having an outer shellformed with a reentrant pocket in the surface thereof for receiving anattachment strut, a bulk head adjacent said pocket and strut securingmeans in said pocket for securing said strut to said shell and bulkhead.

9. In a device of the class described, a pontoon having an outer shellformed with a reentrant pocket in the surface thereor` for receiving anattachment strut, a bulk head adjacent said pocket, strut securing meansin said pocket for securing said strut to said shell and bulk head andstrut securing means adjacent said pocket for securing said strut to.said shell and bulk head.

ln testimony whereof I aiiix my signature.

ARTHUR RALSTON STALB, J n.

